One type of simple ear plug includes a body formed of soft material for pressing into the ear canal to block it. Such ear plugs can be constructed by injection molding a foamable material into a die, which forms a foam body with a smooth thin skin on the outside. However, it has been found that when such an ear plug body is pressed into the ear canal, the skin on the plug body does not uniformly contract, so that wrinkles may be created through which sound can pass to reduce the effectivness of the ear plug. Furthermore, when workers handle the ear plugs by grasping them, they sometimes pinch the outer skin which causes it to crack. The ear plug is often provided with a stem extending perhaps a centimeter behind the plug body to aid in installation and removal from the ear. However, the stem must be soft to minimize danger to the wearer, and the soft stem does not help much in pressing the plug body into the ear. An easily constructed ear plug which avoided wrinkling when pressed into the ear canal or cracking when pinched, and which could be easily installed in the ear, would enable more effective ear plugs to be constructed.